The present invention relates to tricyclic analgesic and anti-inflammatory agents of the structural formula (I). ##STR1## or a pharmaceutically acceptable salt, ester or amide thereof. In addition, the present invention also includes those derivatives which are bioequivalents of compound (I). For example, compounds of formula (Ia) wherein A is --CHO; --CH.sub.2 OH; or --CN. These novel nonsteroidal-anti-inflammatory agents (NSAIA) also exhibit the actions of analgesia and antipyresis. In other words, they are useful for the treatment of fever, pain and inflammatory conditions, associated with arthritis, spondylitis, gout, dismennohrea, upper respiratory disorders and peridontal diseases.
Accordingly the objectives of the present invention are (1) to provide novel nonsteroidal anti-inflammatory and analgesic agents with high potency but lower ulcerogenic side effects; (2) to develop processes for the preparation of the novel tricyclic compounds; (3) to provide methods of application of the novel tricyclic compounds in the treatment of inflammatory diseases and/or the relief of pain and fever; and (4) to provide pharmaceutical compositions and formulations for the administration of these novel tricyclic compounds.